Guide-wire mounted baloon modulation device and methods of use

ABSTRACT

An apparatus for modulating the pressure of a fluid such as a gas within the expandable portion of a guide wire catheter. A preferred embodiment apparatus features a means for controllably gripping and releasing the open, proximal end of a tubular guide wire, means for introducing a fluid to a desired pressure and volume into the expandable portion of the tubular guide wire through the open end, and, while maintaining the pressure and volume of fluid in the tubular guide wire, a means for introducing a sealing member into the open end of said tubular guide wire to seal the fluid in the tubular guide wire. In a particularly preferred embodiment, the apparatus also features a deflation tool for piercing the seal and letting the fluid out. Using this apparatus, the tubular guide wire can be re-sealed and re-opened as necessary.

BACKGROUND OF THE INVENTION

[0001] The invention generally relates to interventional or surgicalprocedures, specifically relating to interventional cardiology and otherintra-luminal procedures. The invention more particularly concerns avalve mechanism that allows modulation of pressure within a balloon orexpandable member attached to, or otherwise located thereon, of aguide-wire or other catheter-like instrument.

[0002] The use of a balloon attached to the end of a guide-wire is notnew, see for example U.S. Pat. No. 6,251,084 (Coelho), and U.S. Pat. No.4,790,813 (Kensey). In this arrangement, the guide-wire is actually asmall diameter tube, with the lumen therethrough serving to allow fluidto be injected, and with the fluid being an agent used to expand theballoon.

[0003] The balloon may serve various functions (e.g., locating and/orsecuring the wire or associated device within the artery, securing awire within a catheter, or blocking the distal flow of fluid and/ordebris created during one or more of the procedures).

[0004] The balloon/guide-wire system may be used in various types oftherapeutic and/or diagnostic procedures (e.g., percutaneoustransluminal angioplasty, stent placement, the placement of ultrasonicor other diagnostic instruments, and the placement of thrombectomydevices, etc.). During the procedure several catheters or elongateinstruments (together “catheters”) may be used sequentially, with thesame guide-wire. Inserting instruments over, or alongside, a singleguide-wire saves procedural time, since only one guide-wire would needto be placed. This approach may also improve safety, and reduce chanceof infection, etc.

[0005] Inserting a plurality of catheters, whether singularly orconcurrently, requires the catheter(s) to be placed over the proximalend of the guide-wire. Where the guide-wire is arranged with a balloonat or near the distal end, the catheter(s) would need to be passed overany valve located at the proximal end of the guide-wire.

[0006] Multiple catheters are commonly used when, for example, aphysician performs an angiogram or other diagnostic procedure, and thendecides to perform angioplasty or other therapeutic procedure or otherinterventional procedure. Most interventional procedures will requirethe placement of a guide wire for the subsequent delivery of theinterventional instruments, and more recently some guide wiresincorporate distal balloons to protect the distal tissues from debrisgenerated during those same procedures. Since treatment and diagnosticprocedures are becoming more commonplace, and the advancements in eachof these technologies have led to procedures using even more catheters.These catheters are continually getting smaller, which allows thephysician to reach tighter arteries and lumens within the body.

[0007] For distal protection to be effective the balloon must remaininflated as catheters are exchanged over the guide wire. Thisnecessitates a small diameter valve, which some refer to as alow-profile valve. Self-sealing valves have previously been disclosed;see for example U.S. Pat. No. 3,477,438 (Allen, et al.), U.S. Pat. No.3,495,594 (Swanson), U.S. Pat. No. 3,837,381 (Arroyo), and U.S. Pat. No.4,752,287 (Kurtz, et al.). These valves are commonly made from elastic(Allen, et al., and Kurtz, et al.) or resilient (Swanson) materials, andmay require pressure in the system to operate (Arroyo). The propertiesof these valve materials, together with their operational pressures,require various of these valves to have large sealing areas. This doesnot facilitate the design of smaller catheters. Additionally, the valveswould ideally operate over a wide range of pressures; including positiveand negative pressures.

[0008] Check valves have also been disclosed, see for example U.S. Pat.No. 4,653,539 (Bell), however these are directional valves, andtherefore will not operate in both positive and negative pressureenvironments. Employing a vacuum in the system during navigation willfacilitate the securing of the balloon to the guide-wire, that is, theballoon will stay folded or otherwise securely pressed against the sideof the wire. This may allow the system to navigate tighter vessels orlumens. However, check valves, such as the one disclosed by Bell, do notmeet this bi-directional operation need. Additionally, this type ofvalve, as well as the previously described self-sealing valves, requirea syringe or special instrument to allow evacuation around the valve'ssealing surface. These syringes or needles must be in-place during theentire evacuation procedure, or the valve will cease the fluid flow.This opens the systems up to situations where malfunctions or equipmentbreakage may yield an inserted and expanded balloon, which may notreadily be collapsed. A system is needed that will allow evacuationwithout the application of vacuum or other specialized components.

[0009] In addition to these stated concerns, the length of time requiredto complete the procedure is affected by these valves. This proceduretime is of concern because of escalating medical costs, as well as thestress on the patient. These valves must allow rapid infusion andevacuation of balloon-filling fluids.

[0010] Yet another low profile catheter valve, designed to fit smalldiameter catheters to navigate small pathways within the body such asblood vessels and ducts, is disclosed in U.S. Pat. No. 4,911,163 (Fina).A syringe is attached to the proximal end of an elongated tubularconduit (e.g. catheter) and used to inflate a distal balloon. Once theballoon is inflated, the catheter is clamped at the proximal end, thesyringe is removed, and a plug is inserted into the lumen of thecatheter, and then the clamp is removed. The plug is retracted andreinserted to adjust the balloon inflation volume as needed, using thissame multi-step procedure. Needless to say, this type of valve istedious to handle and the need for a separate clamping system furthercomplicates the procedure and may potentially damage the catheter.Certainly the clamping pressures are very high, in order to totallycollapse the circular catheter bore such that fluid will not leak (untilthe plug is inserted). Reinflating the balloon would also causeintegrity problems if the catheter were reclamped at the same location.

[0011] Another such low profile catheter valve is disclosed in U.S. Pat.No. 6,325,778 (Zadno-Azizi, et al.). This valve features a needle whichis inserted coaxially with the guide-wire, wherein the needle isarranged to cover a fluid outlet port. The rate of balloon inflation andcollapse is limited by the rate at which gas leaves the fluid outletport. Since the fluid outlet port is radially outward from theguidewire's longitudinal axis, its size is geometrically constrained;that is, the larger diameter of the port, the less strength theguide-wire has. Since the guide-wire must withstand significant bendingand torsional stress during the procedure, the port must besignificantly less than the inside diameter of the guide-wire, therebylimiting the rate of evacuation of the balloon-filling fluid.

[0012] This slow evacuation phenomenon may have been recognized byCoelho, as the disclosure prescribes a vacuum to collapse the balloon.Indeed, the tortuous path in the orifice of the Coelho device, throughwhich the balloon inflation fluid is evacuated, must be nearly as smallas the one disclosed by Zadno-Azizi. Here, the orifice must beconsiderably smaller than the inside diameter of the guide-wire, becausethe path of fluid escape is through a self-sealing valve; and the valvemust have sufficient integrity to cause a seal against itself, after anevacuation needle is withdrawn.

[0013] A valve which may utilize the overall inside diameter (or bore)of the guide wire is disclosed in U.S. Pat. No. 5,807,330 (Teitelbaum).The two basic concepts disclosed by Teitelbaum are a valve that isbasically an insert with threads, wherein the threads secure the valvein the proximal end of the guide-wire; and an insert with a press-fitgeometry, that is pressed into the proximal end of the guide-wire. Bothof these concepts suffer similar shortcomings.

[0014] The threaded insert requires extremely fine threads, which areexpensive and tedious to manufacture even before considering the limitedwall thickness of the guide-wire available for threading (perhaps only afew thousandths of an inch). Additionally, it is extremely difficult toalign small threaded parts of this sort, which leads to misalignment andcross-threading. This problem would be especially prevalent where thesame valve was actuated more than once during the same procedure—acommon occurrence.

[0015] The press-fit geometry requires parts of very tight tolerance,which are also tedious and expensive to produce. Press-fit componentsare normally manufactured for mechanical support, but press-fitting tocause a gas impermeable seal is possible; however, the insert wouldrequire an extremely uniform surface, which mates exactly with theinside surface at the proximal end of the guide-wire. It is thisguide-wire surface which poses great manufacturing challenges.

[0016] Boring or machining the inside surface of the guide-wire is verychallenging because of the fine wall thickness—perhaps only a fewthousandths of an inch. Machining of this component may produceirregular wall thinning, since no tube inside and outside is trulyconcentric, which could lead to premature failure.

[0017] The aforementioned threaded and press-fit concepts disclosed byTeitelbaum both suffer manufacturing challenges as well as economicdisadvantages. Finally, they have features that may lead to prematurefailure, necessitating removal of the device, following by re-insertionof a new balloon/guide-wire assembly.

[0018] It is the intent of the embodiments of the present invention toovercome these and other shortcomings of the prior art.

SUMMARY OF THE INVENTION

[0019] These and other objects of this invention are achieved byproviding a valve mechanism for inflating and deflating a balloon orother expandable member on a guide-wire or catheter (e.g., at or nearthe distal end of a guide-wire), such that while the balloon isinflated, the proximal end of the wire would have a low profile andwould not interfere with the use of other interventional devices usingover-the-wire technique or rapid exchange systems. The system basicallyconsists of detachable tools, one each for inflation and deflation ofthe balloon; additionally the inflation tool features in a preferredembodiment a gripping means, an inflating means, and a sealing means.

[0020] The inflation tool serves the functions of gripping and releasingthe guide wire proximal end; providing a means of modulating thepressure inside the guide wire resulting in balloon or expandable memberinflation; and applying a deformable plug into the bore of the guidewire.

[0021] In use, the proximal end of the guide wire is inserted into achamber of the inflation tool; pressure is introduced via the inflationmeans thereby inflating the balloon or expandable member. The detachableinflation tool inserts a malleable plug in the proximal bore of theguide wire, thereby avoiding the need for costly machining andstringently tight tolerances of other devices, in order to maintainpressure within the guide wire upon the detaching the inflation tool.The sealing means prevents the escape of fluid (e.g., gas or liquid)from the guide wire for the duration of the procedure, or until releaseof pressure becomes necessary.

[0022] The deflation tool serves the function of relieving the pressurein the balloon or expandable member of the guide wire, by piercing thesealing means in the proximal bore of the guide wire, and upon toolremoval allows the fluid contained therein to escape. The valvemechanism herein described allows repeated inflation and deflation ofthe catheter or guide wire, by engaging the appropriate inflation ordeflation tool.

DESCRIPTION OF THE DRAWINGS

[0023]FIG. 1 is a sectional view of one design of tool for applying thesealing plug.

[0024]FIG. 2 is a perspective view of the sealing plug holding rod.

[0025]FIG. 3 is a perspective view of the cam sleeve.

[0026]FIG. 4 is a sectional view of the deflation needle tool prior toapplication.

[0027]FIG. 5 is a sectional view of the deflation needle tool duringapplication.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Description of InflationTool

[0028] The preferred embodiment tool shown in FIGS. 1, 2 and 3, performsvarious functions, including but not limited to:

[0029] a) Gripping and releasing the guide wire proximal end;

[0030] b) Inflating the balloon on the distal end of the guide-wire, orplaced somewhere therealong; and

[0031] c) Applying a sealing member in the proximal bore of the guidewire.

[0032] These various device embodiments comprise sealing means, grippingmeans, and inflation means; while a separate device features deflationmeans. It is recognized that the device arranged for deflation may beattached to the device arranged for inflation (for convenience),although they may not share any componentry other than structural orhousing. Additionally, it is contemplated by this invention that aninflation device or “inflation tool” may not necessarily comprise eachof a gripping means, an inflation means, and a sealing means. As anon-limiting example, it is recognized that the inflation means may be atraditional syringe (where the inflation device was arranged to acceptsame). It is also recognized that the gripping means may be useful toperform other functions (e.g., gripping tubes at diagnostic and/ortherapeutic equipment inlet ports, e.g., those found on bypass anddialysis machines.)

[0033] Referring now to FIGS. 1, 2, and 3, describing a preferredembodiment of the inflation tool, wherein like numbers indicate likecomponents. A preferred gripping means is disclosed, wherein a tubularguide wire 12, enters bore 37 in shaft 18 and passes through deformablemember 19, through pierceable diaphragm 20, into cavity 21, and stopsagainst the face 23A of rod 23. Shaft 18 is slidably mounted in bore 41of housing 28, and, driven proximally (relative to the guide-wire 12) byspring 16, thereby compressing deformable member 19 against the taperedbore 40 in housing 28. Pierceable diaphragm 20 is an intact disc untilpierced by the entering tubular guide wire 12, the purpose of thediaphragm being to capture a charge of fluid (e.g., CO₂ or saline) incavities 45, 21, and channel 35, prior to the piercing by the guide-wire12. Axial compression of the deformable member 19 results in the tubularguide wire 12 being gripped as the deformable member is moved radiallyinward by the taper 40. An alternative to the pierceable diaphragm forretaining the charge of fluid in the cavity 21 and 45 is to ship theassembly with a smooth mandrel gripped in the deformable member 19 (notshown).

[0034] In a preferred embodiment, the gripping means further features aninsertion-release means, wherein the shaft 18 can be driven distally(relative to the guide-wire 12) by movement of lever 15 which, pivotingon pin 14, moves the cone 13 attached to shaft 18. Thus movement of thelever 15 radially inward relieves the pressure on the deformable member19 and hence releases the guide wire 12 (the same feature may also beused in reverse, to assist the entry of the guide-wire into the device,as will be described later).

[0035] In a preferred embodiment the inflation tool features a sealingmeans, with the sealing means arranged to deliver a sealing membermaterial into the guide-wire to effect a seal, as will be describedlater. In this embodiment, the sealing means is preferentially locatedat the proximal end of the device, wherein there exists a mounted rod 23which can move axially and rotationally in bore 21A of housing 28. Rod23 is driven distally by spring 25 acting through flange 24 and isrestrained by arm 26 coming in contact with one of the grooves 42 or 43.An O-ring seal 29 seals rod 23 against bore 21A. A sealing membermaterial 22 is inserted in an off center bore in rod 23. Surface 23A ofrod 23 is striated with grooves (not shown) to permit flow of fluid intothe bore of tubular guide wire 12.

[0036] In a preferred embodiment the sealing member material is madefrom a plastically deformable or inelastic material, wherein suchmaterial may comprise organic and/or inorganic material. It isrecognized that various materials may be suitable for this application,and the totality of material properties (e.g., strength, ductility,thixotropy, toughness, malleability, hysteresis, adhesiveness and fluidpermeability, etc.) may reveal several good candidates.

[0037] In a preferred embodiment the inflation tool features inflationmeans. At the lower portion of FIG. 1 is shown a preferred embodiment ofthe inflation means, comprising an inflation syringe 44, wherein thesyringe contains a barrel 30 arranged to be attached to body 28 usingadhesive or a threaded joint (not shown). The charge of fluid ispre-charged into cavities 45, 21 and 35. A piston 31 attached to aplunger 32 drives fluid (gas or liquid) from chamber 45 via channel 35into chamber 21 and thence into tubular guide wire 12. Another preferredembodiment additionally features a latch 33 fastened to barrel 30,wherein the latch 33 engages flange 34 after the plunger has been movedinward to deliver the fluid. The latch serves to prevent the piston andplunger from being driven back by the pressure trapped in cavity 21(etc.) and balloon 11.

Description of Inflation Tool Use

[0038] A preferred embodiment inflation tool includes the gripping,inflation, and sealing means in combination, and allows the operator tohold the assembly 1 in one hand and with the thumb and fore-finger tosqueeze the lever 15 toward the body 28 thus moving shaft 18 distallyand relieving pressure on the deformable member 19. The guide wire 12 isthen inserted into shaft 18, centralized by the tapered inlet 38, passedthrough the deformable member 19, to pierce the diaphragm 20 and come torest against rod 23 at surface 23A. Chamfers at 39 and 36 further aid incentralizing the guide wire. Surface 23A of rod 23 is striated with finegrooves (not shown) to permit flow of fluid into the bore of tubularguide wire 12. When the guide wire has bottomed on surface 23A, the userreleases the lever 15, whereupon the shaft 18 is propelled to proximallyand deformable member 19 is placed in compression. In turn this action,through taper 40, causes the deformable member 19 to grip the guide wire12 securely.

[0039] In a preferred embodiment, the position of the guide wire may beconfirmed visually by viewing the location via the lens 46 built in to aclear plastic housing 28. Alternatively, if the housing is made from anopaque material the viewing lens 46 can be inserted in a tunnel as aseparate component (not shown).

[0040] In yet another embodiment, the correct position of the guide wire12 can alternatively be ascertained by observing the location of acontrasting band of color 60, formed on the guide wire 12, relative tothe entrance 61 of shaft 18.

[0041] Now returning to the preferred combination embodiment, theplunger 32 and attached piston 31 are then driven inward to propel thefluid in cavity 45 through channel 35 into cavity 21 and thence throughthe bore of guide wire 12 into the balloon 11. In the case where gas isused to inflate the balloon, the plunger 32 may be driven to the bottomof the bore and allowed to return to a position controlled by flange 34and latch 33. This over-compression of the gas permits the initialpressure to be high to overcome the balloon resistance but drops thepressure as the balloon reaches full size, thus reducing the tendency tooverpressure the vessel (not shown) in which the balloon is residing.

[0042] With the balloon 11 inflated in the vessel, the arm 26 is rotated180 degrees in this example (but any other angle would work with slots42 & 43 placed differently) so that rod 23 revolves to place the sealingmaterial 22 to a position opposing the guide wire 12. Then spring 25urges rod 23 distally and drives the sealing material 22 into the openend of tubular guide wire 10 thus trapping the fluid in the guide wireand balloon. A plug 50 of sealing material 22, is driven into the boreof the tubular guide wire 12, as shown in FIG. 4.

[0043] At this point the lever 15 is again pressed inward radially andthe guide wire is removed from the device, and the wire is ready for therest of the interventional procedure, which might involve the passage ofangioplasty balloons, stent balloons, diagnostic ultrasound, or otherprocedure requiring a balloon protected or anchored guide wire with theballoon inflated.

Description of Deflation Tool

[0044] Referring to FIGS. 4 and 5, a preferred embodiment of thedeflation tool 56 is basically constructed from four elements, a handle51, a tube 54, a spring 52, and a needle 53. The handle has a bore 57 ofabout 0.016 inch diameter, a little larger than the outside diameter ofthe guide wire 12 which is typically 0.015 inch, and has a lead in taper55 to allow the operator to easily locate the bore 57.

[0045] The proximal end (relative to the user's hand while utilizing thetool) of the needle 53 is held centrally in the bore 57 by tube 54. Tube54, together with the needle 53, and the handle 51 can be assembledtogether by any convenient means, including but not limited to welding,using an adhesive, or a crimping operation. The needle is approximately0.005 inch in diameter in this embodiment, and is supported by thespring coils 52 to prevent the needle from being bent during use and toalign the distal end (relative to the user's hand while utilizing tool)of the needle on the centerline of the bore 57. The length of the plug50 of sealing member material 22 (see FIG. 1) in the proximal end of theguide wire 12 is preferably about 0.030 inch long axially, althoughother dimensions may be more suitable depending on the composition ofthe sealing material and the pressure at which the balloon requires. Theguide wire outside diameter 59 is typically 0.015 inch and the bore 58can typically range from 0.011 inch to 0.005 inch. The needle needs tobe sufficiently large to provide a bore through the plug 50 that it willallow the balloon to be deflated rapidly, but not so large that the plug50 is smeared along the bore 58 too far to require a very long needle.It has been found that a 0.005 inch diameter needle permits deflationtimes that are acceptable (less than 30 seconds), utilizing a 0.007 inchdiameter guide wire bore. Clearly these dimensions are examples only andcould be adjusted to accommodate guide wires or catheters of differentdiameters.

[0046] The deflation tool embodiment described can be used multipletimes, but it is unlikely that the operator will ever need to inflateand deflate the balloon more than 5 times in a procedure. The needle 53is therefore preferably required to penetrate several times the lengthof the plug 50 into the guide wire bore 58 for this to be achieved.

Description of Deflation Tool Use

[0047] The operator inserts the proximal end of the guide wire 12 intothe lead taper 55 of the deflation tool 56 compressing the spring 52 tothe fully compressed condition. The plug 50 is pierced as shown in FIG.5, and smears into an elongated tubular shape 62 concentric to the bore57. The balloon 11 (see FIG. 1) then deflates due to its inherentelastic recovery, and/or vacuum can be applied to the tubular guide wire12 by syringe or other means (neither shown) to accelerate the deflationtime. The tool is then removed and is available for any subsequent use.

[0048] Thus since the invention disclosed herein may be embodied inother specific forms without departing from the spirit or generalcharacteristics thereof, some of which forms have been indicated, theembodiments described herein are to be considered in all respectsillustrative and not restrictive, by applying current or futureknowledge. The scope of the invention is to be indicated by the appendedclaims, rather than by the foregoing description, and all changes whichcome within the meaning and range of equivalency of the claims areintended to be embraced therein.

What is claimed is:
 1. An apparatus for modulating the pressure of afluid within the expandable portion of a guide wire catheter, theapparatus comprising an inflation tool comprising: means forcontrollably gripping the open, proximal end of a tubular guide wire;means for introducing a fluid into said expandable portion of saidtubular guide wire through said open end, thereby inflating saidexpandable portion of said tubular guide wire to a desired extent; andwhile maintaining said expandable portion inflated to a desired extent,providing a sealing means for introducing a sealing member into saidopen end of said tubular guide wire to seal said fluid in said tubularguide wire.
 2. The apparatus of claim 1, further comprising a means forre-opening said proximal end of said tubular guide wire.
 3. Theapparatus of claim 1, wherein said sealing member comprises wax.
 4. Theapparatus of claim 1, wherein said means for introducing said sealingmember comprises a rod mounted in said apparatus, said rod being capableof moving axially and radially.
 5. The apparatus of claim 4, whereinsaid sealing member is housed in a bore in a flat surface of said rodthat is to contact said open end of said tubular guide wire, said borebeing offset from a longitudinal axis of said rod.
 6. The apparatus ofclaim 5, wherein said open, proximal end of said tubular guide wire isurged against said flat surface.
 7. The apparatus of claim 5, whereinsaid flat surface is striated to permit fluid to enter said tubularguide wire through said proximal end when said guide wire is in contactwith said flat surface of said rod.
 8. The apparatus of claim 6, whereinsaid sealing means comprises gripping said proximal portion of saidtubular guide wire, rotating said rod until said bore containing saidsealing member comes into alignment with said proximal end of saidtubular guide wire, and pressing said rod axially toward said tubularguide wire, thereby pressing said sealing member into said proximal endof said tubular guide wire.
 9. The apparatus of claim 2, wherein saidmeans for re-opening said proximal end of said tubular guide wirecomprises a deflation tool comprising a needle for piercing said sealingmember.
 10. The apparatus of claim 9, wherein said deflation toolfurther comprises a tube open on at least one end, said opening definedby a bore, and wherein said needle is mounted in said bore coaxiallywith a centerline of said bore.
 11. The apparatus of claim 10, furthercomprising a lead-in taper to said bore, and a spring to help supportsaid needle.
 12. The apparatus of claim 10, wherein said needle arrangedin said bore creates a channel between said needle and an inner wall ofsaid tube, said channel having a spring arranged therein such that saidspring maintains concentricity of said needle in said bore.
 13. A valvemechanism for modulating pressure in a balloon or expandable member onor about a catheter or guide wire, the valve mechanism comprising; a) aninflation tool, the inflation tool comprising a gripping means, thegripping means comprising a deformable member and a deforming mechanism,the deforming mechanism acting upon the deformable member to causegripping of the catheter or guide wire; an inflating means, theinflating means comprising a charge of fluid, and a means of modulatingthe pressure of the charge of fluid, and a pierceable barrier to preventpremature leakage of the charge of fluid; a sealing means; the sealingmeans comprising a plug, the plug being of a material suitable forsealing and maintaining pressure in the guide wire or catheter, and aninsertion rod, the insertion rod facilitating the insertion of the pluginto a guide wire or catheter; b) a deflation tool, the deflation toolcomprising a needle, the needle upon application penetrating the sealingmeans to allow pressure relief of the expandable member, and a handle,the handle arranged to manipulate the needle.
 14. The valve mechanism ofclaim 13, wherein said deflation tool further comprises a compressiblematerial around said needle, with said needle being arranged within saidhandle, said compressible material preventing said needle fromdeflecting upon use.
 15. The valve mechanism of claim 13, wherein saiddeflation tool further comprises a compressible spring around theneedle, with said needle being arranged within said handle, saidcompressible spring preventing the needle from deflecting upon use. 16.The valve mechanism of claim 13, wherein said sealing means comprises aplastically deformable and not elastically resilient material.
 17. Thevalve mechanism of claim 13, wherein said inflating means furthercomprises a syringe device to modulate the pressure of the charge fluid.18. The valve mechanism of claim 13, wherein said gripping means furthercomprises a lever mechanism arranged to displace said catheter or guidewire while acting upon said deformable member.
 19. The valve mechanismof claim 13, wherein said insertion rod comprises a striated face, aninset plug of deformable material, and a lever for actuating saidinsertion rod.